Oliver, did you read the article I linked to? Specifically the "meet Rosa" section? That is one way, at a cost, that TCA can be reduced.

But I don't want to be seen as an apologist for the cork industry. What I would like to see are substantiated figures showing percentages of bottles with detectable TCA after treatment. IMO anything higher than something like 0.01% is unacceptable. Also, considering that the cork industry play on they green credentials compared with screwcap, I'd be interested in knowing how the additional processes affect the environment.

Normally we store corked bottles on their side so like Mark L stated when air molecules inside the cork get dissolved in the wine and a void is created, something has to take its place. Either the air molecules inside the cork itself shift positions, of course this will leave voids some where else until it gets to the outside surface of the cork where eventually air molecules from the atmosphere will ingress into the cork. Another scenario is that the wine itself could “take up” the space left by the dissolving air molecules.

Oliver McCrum wrote:With respect, Robin, I think that this is misleading. You appear to be suggesting that cork taint would be substantially reduced if producers were prepared to pay more; I know this isn't the case for my producers, and I suspect it isn't true generally. The blame for this problem can't be shifted to the customers, it remains squarely with the producers.

Oliver, I'm not sure I completely understand your point here as you seem to be saying something with which I agree in part and disagree in part.

In no way would I suggest that blame be shifted to the consumer, who is the victim in all this.

I do believe, however, that certain quality producers - specifically Amorim - are fully aware of the taint problem and, under new generation management over the past decade are doing all they can to fight it, both with technology and, of course, publicity.

I am absolutely certain that it is not possible to eliminate all taint from natural cork. I do believe that extreme quality control - and, for "manufactured" cork, such technologies as ROSA - can go a long way to reduce it. I do not agree that quality manufacture shows only in appearance.

And I do very much believe that some producers are neither willing, able or ready to pay the price for high-quality cork to reduce the incidence of taint. Too many producers are too willing to write off a 5 percent failure rate.

All that said, my personal experience - and I open a fair amount of wine - is that taint in my experience has fallen off from more than 5 percent to about 1 percent over the past few years, without alternative closures being taken into account.

I know a lot of people in the business HATE natural cork, and based on your posts I would respectfully submit that you likely fall into that category. Fair enough. But it's really best not to allow emotion to override logic.

Victorwine wrote:Normally we store corked bottles on their side so like Mark L stated when air molecules inside the cork get dissolved in the wine and a void is created, something has to take its place. Either the air molecules inside the cork itself shift positions, of course this will leave voids some where else until it gets to the outside surface of the cork where eventually air molecules from the atmosphere will ingress into the cork. Another scenario is that the wine itself could “take up” the space left by the dissolving air molecules.

Another is that the pressure inside the bottle is reduced by a little bit compared with what it would be otherwise. No big deal in that - remember air only contains around 20% orxygen anyway.

Robin Garr wrote:I am absolutely certain that it is not possible to eliminate all taint from natural cork. I do believe that extreme quality control - and, for "manufactured" cork, such technologies as ROSA - can go a long way to reduce it. I do not agree that quality manufacture shows only in appearance.

Quality manufacture obviously doesn't only show in appearance, but my point is that at I have never seen a pricing option for bark cork that says 'pay more and we'll guarantee <3% <1ppt.' One listing from Scott Labs, for example, says

'These natural corks have received a light hydrogen peroxide and water wash followed by neutralizing rinses. Corks are then dried to a moisture level between 5 and 8%. They are, quite simply, the cork standard.

Unless I miss my guess those 'qualities' have to do only with appearance, not with freedom from taint. Scott Labs do talk about their overall cork QC programs, but you can't pay more for a given cork and get lower taint rates.

And I do very much believe that some producers are neither willing, able or ready to pay the price for high-quality cork to reduce the incidence of taint. Too many producers are too willing to write off a 5 percent failure rate.

This is a straw man, and I still think you're shifting the blame to the wineries and away from the cork producers, where it belongs. Show me a quality winery unwilling to pay more for lower taint; for that matter show me where Amorim or anyone else offers expensive natural cork with anything like a normal 2008 failure rate, at any price. All of my producers are frustrated by cork problems, and many of them pay through the nose for cork. So this particular group of wineries is prepared to spend a small fortune for corks every year, and still suffer from failure rates that would be absurd in any other business.

All that said, my personal experience - and I open a fair amount of wine - is that taint in my experience has fallen off from more than 5 percent to about 1 percent over the past few years, without alternative closures being taken into account.

Your experience isn't consistent with what the cork producers themselves admit is the normal failure rate; for example, a report issued in 2006 by the 'Cork QC Council' stated 'the vast majority of CQC natural corks are now below 2ppt (94%).' Which is to say they admit that 6% are over 2 ppt. My threshold is about 2 ppt, yours may be lower. And we are only talking about TCA here, if we include failures like Random Oxidation or sparkling wine problems it's higher.

And this illustrates one of the things that strikes me as suspect with many industry 'improvements', which is that their standard for 'TCA free' is often 2 ppt. Did they set that level because they thought no-one can smell 2 ppt, or because with the current technology that's the best they can do?

I know a lot of people in the business HATE natural cork, and based on your posts I would respectfully submit that you likely fall into that category. Fair enough. But it's really best not to allow emotion to override logic.

Respectfully, this is a non-sequitur ('hatred of something proves illogic'); anger is a perfectly normal reaction to an infuriatingly high, avoidable failure rate in a product that you love. My understanding of that failure rate, however, is entirely intellectual. As I would have thought this thread would have made clear. If more than one bottle in every two cases broke spontaneously I would be equally pissed.

Robin wrote:All that said, my personal experience - and I open a fair amount of wine - is that taint in my experience has fallen off from more than 5 percent to about 1 percent over the past few years, without alternative closures being taken into account.

Oliver wrote;Your experience isn't consistent with what the cork producers themselves admit is the normal failure rate; for example, a report issued in 2006 by the 'Cork QC Council' stated 'the vast majority of CQC natural corks are now below 2ppt (94%).' Which is to say they admit that 6% are over 2 ppt. My threshold is about 2 ppt, yours may be lower. And we are only talking about TCA here; if we include failures like Random Oxidation or sparkling wine problems it's higher.

IMHO I think Robin’s experience is consistent with the finding of the Cork Quality Council. Robin’s personal threshold for TCA detection might be higher than Oliver’s 2 ppt .threshold for TCA detection. At what ppt of TCA does one experience just muted fruit flavors and aroma or wet concrete, musty wet cardboard and Clorox?

But the issue of TCA detection thresholds leaves out the problem of wines that are rendered fruitless and boring by low-level TCA. Sure someone may be able to detect obvious TCA at 2 ppt, but what about the bottles that just aren't right (from slightly lower levels)?

I’m sure with modern day lab equipment concentrations of lower than 2ppt of TCA can be detected. Will technology eliminate this TCA problem totally? Probably not. There is always that chance that TCA taint could be detected in a package of veggies or bottled water taken from the shelf of the grocery store. So what the food and drug administration has to do is come up with an acceptable level. Now if TCA was proven to be a “health risk” to those who consumed it, elimination of the compound totally is the only solution.What’s so bad about a “little concentration” of TCA subduing some of the fruitiness (not eliminating it totally) and “complimenting” it with a little “earthiness”? Heck, I may find this wine a little more “complex” and “interesting”.

It may be that there isn't any way for the producers to reliably clean cork, and that 2ppt is the best they can do. We are stuck in the early 20th century with cork, it's a striking anachronism; when was the last time you saw a bottle of medicine with a cork in it?

Who says at 2ppt or less in a particular wine I’m going to experience “moldy basement”? Maybe for a given type and style of wine all I experience is a slight reduction in the wine’s fruitiness and a hint of some “moldy”, “mushroom” or “earthy” character.

Victorwine wrote:Who says at 2ppt or less in a particular wine I’m going to experience “moldy basement”? Maybe for a given type and style of wine all I experience is a slight reduction in the wine’s fruitiness and a hint of some “moldy”, “mushroom” or “earthy” character.

Victorwine wrote:What’s so bad about a “little concentration” of TCA subduing some of the fruitiness (not eliminating it totally) and “complimenting” it with a little “earthiness”? Heck, I may find this wine a little more “complex” and “interesting”.

I assume all the quotation marks mean you're playing devil's advocate?

Going full circle back to the topic of this thread, the only way to know is to compare the same wine in cork and in screwcap. I did that yesterday and can say in this case, the answer was YES!Notes posted in a new thread. viewtopic.php?f=3&t=17340

Going full circle back to the topic of this thread, the only way to know is to compare the same wine in cork and in screwcap. I did that yesterday and can say in this case, the answer was YES!Notes posted in a new thread. viewtopic.php?f=3&t=17340

Cheers,Sue

Good work Sue! Inspired by this discussion, I have ordered "To Cork or Not to Cork" from Amazon (along with Kermit Lynch's "Adventures on the Wine Route") - good vacation reading I'm sure.